Permitting you haven't bought a new pair, I just picked these up as I was looking for an upgrade for my Sennheiser PC151's as well.
Personally, I'm considering returning them. It's not that they don't sound great, but considering the whole ordeal of a USB headset not making use of your soundcard (I'm using the X-Fi Xtreme Music sound card) as it has it's own internal card.
I mainly play FPS shooters, and IMHO, found the sound in my 151's combined with my soundcard better than the Corsair's . The hunt for a better gaming headset with ANALOG connectors continues.... Even tried dumping $200 on the Sennheiser PC350's and found that the sound was "distant"....returned as well. Finding it hard to break away from my present set.